He had been swimming for approximately 4,000 yards before trying to complete a "100" — which is four laps underwater without surfacing for air.

After some time, Ramsden's sister realized he wasn't moving underwater. Lifeguards were notified and deputies were called on to the scene of a possible drowning.

Three lifeguards who were on duty told authorities they all "administered rescued efforts" before the fire department arrived to try to save the athlete to no avail.

The Sarasota YMCA said it would be launching a full investigation into the incident, releasing the following statement:

"Our thoughts and prayers go out to this man's family at this time. This event is nearly impossible to comprehend, and he and his family are in our hearts…We are immediately launching an investigation into the incident and are cooperating with all local authorities in their investigations."

Ramsden started competitively swimming at the age of six, becoming a key swimmer at the Nashville Aquatic Club throughout high school.

An autopsy is being completed to determine the exact cause of death. Our hearts go out to the athlete's loved ones at this devastating time.